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This paper focuses on the influence of key components in biomass ash on the gasification reactivity of coal by using simulated biomass ash. The migration patterns of typical biomass ash components and the structural evolution characteristics of coal during gasification process were deeply investigated. The results indicate that gasification temperature and Si element content are the key factors affecting gasification reactivity of coal. When the Si/K mass ratio is 0.5 and 1.0, gasification reactivity of the composite coal sample is stronger than that of raw coal, while the Si/K mass ratio is 1.5, gasification reactivity is weaker than that of raw coal. Under the experimental conditions, the composite coal sample with a Si/K mass ratio of 0.5 and a Ca/K mass ratio of 0.4 shows the strongest reactivity. The gasification reactivity index is 1.35 times higher than that of raw coal. Compared to potassium-containing minerals, calcium-containing minerals have stronger reactivity and are more likely to react with silicates to form calcium-containing silicates, such as calcium zeolites (CaO·Al2O3·2SiO2·4H2O), thereby avoiding the reaction between potassium-containing minerals and silicates to form non-catalytic minerals, which allows potassium to fully exert its catalytic effects. Dynamic analysis implies that shrinking core model well describes the gasification process of deashing coal catalyzed by simulated biomass ash. When the Si/K mass ratio is 0.5 and the Ca/K mass ratio is 0.4, the activation energy of composite coal sample is reduced to 174.39 kJ/mol, which is 14.32% lower than that of raw coal. This paper focuses on the influence of key components in biomass ash on the gasification reactivity of coal by using simulated biomass ash. The migration patterns of typical biomass ash components and the structural evolution characteristics of coal during gasification process were deeply investigated. The results indicate that gasification temperature and Si element content are the key factors affecting gasification reactivity of coal. When the Si/K mass ratio is 0.5 and 1.0, gasification reactivity of the composite coal sample is stronger than that of raw coal, while the Si/K mass ratio is 1.5, gasification reactivity is weaker than that of raw coal. Under the experimental conditions, the composite coal sample with a Si/K mass ratio of 0.5 and a Ca/K mass ratio of 0.4 shows the strongest reactivity. The gasification reactivity index is 1.35 times higher than that of raw coal. Compared to potassium-containing minerals, calcium-containing minerals have stronger reactivity and are more likely to react with silicates to form calcium-containing silicates, such as calcium zeolites (CaO·Al2O3·2SiO2·4H2O), thereby avoiding the reaction between potassium-containing minerals and silicates to form non-catalytic minerals, which allows potassium to fully exert its catalytic effects. Dynamic analysis implies that shrinking core model well describes the gasification process of deashing coal catalyzed by simulated biomass ash. When the Si/K mass ratio is 0.5 and the Ca/K mass ratio is 0.4, the activation energy of composite coal sample is reduced to 174.39 kJ/mol, which is 14.32% lower than that of raw coal.

Perfluoride glass ceramics (FGCs) with SrF2/CaF2 mixed crystals were prepared using a concurrent rapid-quenching-crystallization process. The FGCs contained dense, homogeneous, round crystals of sizes less than 1 μm with high transmittance (exceeding 80% at 3-8 μm) and low phonon energy (508 cm-1). The fluorescence properties of the FGCs doped with Er and Dy were investigated. The energy transfer efficiency between Er and Dy reached 93.81% and 98.13%, corresponding to Er: 4I11/2 to Dy: 6H5/2 and Er: 4I13/2 to Dy: 6H11/2, respectively. This enhancement is attributed to the enrichment of rare-earth ions in the crystals induced by phase-separation and low phonon energy of the host material, FGC. Moreover, the average lifetime of Er: 4I11/2 in FGC reached 10.13 ms, which is the highest reported value for glass ceramics to our knowledge. This study enriches the research theory of FGC and provides guidance for expanding the properties of materials for mid-infrared photonics. Perfluoride glass ceramics (FGCs) with SrF2/CaF2 mixed crystals were prepared using a concurrent rapid-quenching-crystallization process. The FGCs contained dense, homogeneous, round crystals of sizes less than 1 μm with high transmittance (exceeding 80% at 3-8 μm) and low phonon energy (508 cm-1). The fluorescence properties of the FGCs doped with Er and Dy were investigated. The energy transfer efficiency between Er and Dy reached 93.81% and 98.13%, corresponding to Er: 4I11/2 to Dy: 6H5/2 and Er: 4I13/2 to Dy: 6H11/2, respectively. This enhancement is attributed to the enrichment of rare-earth ions in the crystals induced by phase-separation and low phonon energy of the host material, FGC. Moreover, the average lifetime of Er: 4I11/2 in FGC reached 10.13 ms, which is the highest reported value for glass ceramics to our knowledge. This study enriches the research theory of FGC and provides guidance for expanding the properties of materials for mid-infrared photonics.

Segmentation of prostate magnetic resonance images is of great significance in the interventional diagnosis and treatment of prostate diseases. In this work, the conventional distance regularized level set evolution (DRLSE) model is improved and applied to prostate segmentation. In magnetic resonance image, the prostate boundary near the bladder is often blurred, while that near the urethra is clear, resulting in a poor performance for the traditional gradient information indicator function. In this study, two indicator functions were used to control the evolution of boundary in the clear segment and blurred segment, respectively, to achieve better segmentation. In addition, an energy check term was added to the external energy function to prevent evolution from stopping at a false boundary. This modification could drive the level set to move to regions with large gray level fluctuation and stop evolution at a blurred boundary. Experimental results demonstrated that the performance of prostate segmentation was satisfactory, judging from the Dice similarity coefficient (DSC) which reached an average of 96%.